This microcomputer-based universal frequency counter satisfies virtually all frequency measurement requirements. The high accuracy concept, high frequency range and powerful measuring features make this counter ideal for rsearch and development of telecom, broadcast, TV, radio control and navigation equipment.

FEATURES:
• High resolution frequency measurements
• Error-free triggering
• High stability crystal oscillators
• High 10 mV sensitivity
• Multiple burst frequency avg
  
  Type 6676/521:
  PM6676 same as 6673 (standard oscillator 5 x 10^-7/month) but with frequency range of 1.5 GHz
  /521 =
• Option 5 - 1.5 GHz Input Frequency
• Option 2 - TCXO Reference Oscillator
• Option 1 - Standard non GPIB IEEE488 Interface
• Option 9679E/01 Adds Ovenized Crystal Oscillator BUT not sure if our option 9679 is the same.

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